Download your desired wallpaper onto a USB stick ensuring it is in a JPEG file format and the size of the file no smaller than 1080p. Insert the USB into the front inputs on the panel. On the CommBox home screen select the Apps icon and scroll to locate and open the 'files' icon.
On the left collum the name of your inserted USB should be displayed.
Press on the USB name to open up the files and hold your finger on the image you wish to use for the wallpaper. On the right hand menu select the option to 'copy'.
On the left hand menu open the 'local' folder and from here open the 'pictures' folder. The right menu will give you the option to 'paste' the file.
User arrows on left or right side of screen to open the menu and select the wheel cog to open settings.
From this menu again select the wheel cog.
The top option will say 'wallpaper', open this and scroll down to the 'pictures' folder where you have saved your picture.
Select 'sdcard' and scroll down to 'pictures'. From here you will be able to select your desired wallpaper.